The use of bone plates for a variety of orthopedic applications is widely practiced. The plates are used to align, mend, and/or alter adjacent bony segments in a patient using a plurality of fasteners such as screws installed through openings in the plate. Correct orientation and alignment of fasteners can be important to proper engagement and positioning of the bone plate relative to the bony segment to which it is engaged.
Bone plates used in spinal applications can be particularly sensitive to positioning and engagement to bony segments of the spinal column. Spinal bone plates can be used for long term, intravertebral and intervertebral fixation and stabilization. Because of the spinal cord and other sensitive anatomical structures adjacent the spinal column, and the relatively small size of the vertebral areas, the desired areas of positioning and alignment of bone engaging fasteners to secure the bone plate to the particular bony segment of the spinal column can be relatively small. A guide assembly capable of maintaining alignment of surgical instruments with respect to a bone plate during engagement of the bone plate to a bony segment is desired.